The present invention is related basically to restraints for control surfaces of grounded or stored airplanes and more particularly to such restraints for preventing movement of the airplane rudder about its normal pivot axis.
Aircraft stored adjacent to a landing field are often subjected to extremely strong gusts of air from the prop wash of other airplanes in the process of taking off or landing. The rudders of grounded aircraft are very susceptible to damage in such high velocity air currents. It is therefore desirable to obtain some apparatus for securing the rudder against such movement when the airplane is in a stored or parked condition.
This problem has been realized to a certain degree by U.S. Pat. No. 3,288,401 to C. Fete which discloses an aircraft rudder lock structure. This device utilizes a pair of rigid bars connected at ends to form a V-shaped member. Clamps are attached to the extremities of the connected bars. Two end clamps are utilized to secure the device to the elevator surfaces while the central clamp is connected to the rudder. Wind force against the rudder is transferred through the rigid bars to the elevators. For example, wind coming in a lateral direction and striking flush against the rudder surface would result in a downward force on one of the bars while the other would be lifted upwardly. If the wind force were excessive, not only could serious damage be done to the rudder, but also to the elevators which are ordinarily intended to move in the same direction.
It is a primary object of the present invention to provide a rudder restraint whereby the rudder may be held against pivotal movement by restraint members connected to the leading edges of the horizontal stabilizers.
It is a further object to provide such a restraint that is very simple in construction and inexpensive to purchase.
It is a still further object to provide such a restraint that may be utilized by differing styles and sizes of airplanes without requiring adjustment.
These and still further objects and advantages will become apparent upon reading the following description which, taken with the accompanying drawings, describe a preferred form of the present invention.